Service Bulletin 164 - Battery Draw

[LB_3]

Originally Posted by amirm

Me too . Mine will arrive in a week or so and then I can test.


I looked everywhere but could not find the DC on resistance. That loss worries me some. The FET switches should have low resistance but that large heatsink tells me it will draw some power. Did you see that spec on their sheet and somehow I missed it?

Right now I am running on stock system and the Micro is not on the inverter.

If I remember correctly the ON current draw is maybe 60 miliamps and the resistance is about .0023 ohms. (Based on the published voltage drop at 150A.) The resistance only becomes an issue with the inverter maxed when the microwave is in use but that isn't the kind of thing that runs for hours at a time.

[lewster]

Originally Posted by Mcrider

If your unit has the Magnum battery temperature sensor make sure you get the "6" conductor coupler as instructed in the installation guide. Otherwise it will not work. I had to do some running around to find a coupler with all "6" conductors

Where did you get the spec. for a 6 conductor coupler? All of Magnum's cables, whether for the temperature sensors, network communication cables or data cables from the inverters to the remotes use 4 conductor cables with 4 conductor RJ-11 plugs at the terminations. I shorten these cables on a daily basis and have never seen Magnum use a 6 conductor cable or termination plug.

[Mcrid]

Originally Posted by lewster

Where did you get the spec. for a 6 conductor coupler? All of Magnum's cables, whether for the temperature sensors, network communication cables or data cables from the inverters to the remotes use 4 conductor cables with 4 conductor RJ-11 plugs at the terminations. I shorten these cables on a daily basis and have never seen Magnum use a 6 conductor cable or termination plug.

The DC Disconnect cable is 6 conductor and the instruction manual that came with it emphasis the coupler to be 6 conductor. You are correct on the temp sensor and remote being four conductor.

[J&J In A Can]

The control signal for the MM-DCLD is 12VDC/OPEN. Magnum is probably using one of the two, usually not present, outside conductors in the 6-conductor jacks/plugs. I found the 6-conductor splitter on Amazon for about $5.

I have to wonder why Airstream took the nuclear option of a relay that needs to conduct ALL of the current to the inverter as opposed to using the MM-DCLD to turn it on and off. Does anyone have any insight into that?

[Boxster1971]

Originally Posted by Mcrider

The DC Disconnect cable is 6 conductor and the instruction manual that came with it emphasis the coupler to be 6 conductor. You are correct on the temp sensor and remote being four conductor.

There are three telephone connectors that will fit in this size port, RJ-11, RJ-14 and RJ-25.

https://en.m.wikipedia.org/wiki/Registered_jack


- - Mike
2013 Lounge EXT on 2012 Sprinter

[Boxster1971]

Originally Posted by LoveToWander

The control signal for the MM-DCLD is 12VDC/OPEN. Magnum is probably using one of the two, usually not present, outside conductors in the 6-conductor jacks/plugs. I found the 6-conductor splitter on Amazon for about $5.

I have to wonder why Airstream took the nuclear option of a relay that needs to conduct ALL of the current to the inverter as opposed to using the MM-DCLD to turn it on and off. Does anyone have any insight into that?

Lack of real engineering talent. A simple call to their supplier, Magnum Energy could have solved their problem of Inverter/Charger parasitic load. Magnum has had this DCLD device around for some time, it's not a new item.


- - Mike
2013 Lounge EXT on 2012 Sprinter

[lewster]

Originally Posted by Mcrider

The DC Disconnect cable is 6 conductor and the instruction manual that came with it emphasis the coupler to be 6 conductor. You are correct on the temp sensor and remote being four conductor.

Ahhhhh, the DCLD. I never use them as I always use a Blue Sea Systems M-Series disconnect switch in all of my inverter installations.

Ya learn something new every day!!!!


Lew Farber
RVIA/RVDA Nationally Certified Master Tech
ABYC Certified Master Marine Electrician
Master Tech Energy Systems, Inc.
AM Solar Certified Installation Center*AMS Lithium Batteries
Lifeline AGM Batteries**Magnum Inverters***Victron Energy Components
541-490-6357

[Mcrid]

Originally Posted by lewster

Ahhhhh, the DCLD. I never use them as I always use a Blue Sea Systems M-Series disconnect switch in all of my inverter installations.

Yes your solution is best when you want a complete disconnect. In fact my two T24s on the bench have maintained over 13 volts for a week sitting on the bench. The DCLD is a good compromise when out and about, just hit the Main disconnect and and you are conserving. For long-term your solution is far more appropriate.

I'm studying the GBS Lithium really hard and the silicon heaters. Once I get a design I'm satisfied taking the risk on I'm in. My design criteria is the Batteries need to be under the coach. I do not want to give up space in the Coach. The 300 Watts solar and 320 AH will get a work-out 23 June - 12 July so I will report. I'll either be set or have 4 24Ts for sale

[LB_3]

Originally Posted by Mcrider

I'm studying the GBS Lithium really hard and the silicon heaters. Once I get a design I'm satisfied taking the risk on I'm in. My design criteria is the Batteries need to be under the coach. I do not want to give up space in the Coach. The 300 Watts solar and 320 AH will get a work-out 23 June - 12 July so I will report. I'll either be set or have 4 24Ts for sale

Since you mentioned it, I'll start a thread this weekend to share the direction I'm headded.

[Boxster1971]

Originally Posted by LB_3

Since you mentioned it, I'll start a thread this weekend to share the direction I'm headded.

Great - looking forward to learn more about your project.


- - Mike
2013 Lounge EXT on 2012 Sprinter

[jim.waters]

Has anyone thought about installing a toggle switch on the DCLD easily accessible inside the cabin? There are lots of times the inverter may not be needed, but the 12v would. This would save .4 amps and still permit use of most things. The DCLD wiring schematic shows an ignition switch. This could be a toggle switch or even a separate breaker on the 12v panel.

[Mcrid]

Originally Posted by jim.waters

Has anyone thought about installing a toggle switch on the DCLD easily accessible inside the cabin? There are lots of times the inverter may not be needed, but the 12v would. This would save .4 amps and still permit use of most things. The DCLD wiring schematic shows an ignition switch. This could be a toggle switch or even a separate breaker on the 12v panel.

You don't need to. You can turn the inverter off from the Magnum remote without shutting down the 12 v system. The DCLD just avoids the mistake of leaving the inverter on when you mean to have the House in a minimum usage state.

[Boxster1971]

Originally Posted by jim.waters

Has anyone thought about installing a toggle switch on the DCLD easily accessible inside the cabin? There are lots of times the inverter may not be needed, but the 12v would. This would save .4 amps and still permit use of most things. The DCLD wiring schematic shows an ignition switch. This could be a toggle switch or even a separate breaker on the 12v panel.

Jim - that's what I plan to do once I get my DCLD and make a few measurements to see if it will save enough to have it on its own switch. I have a total disconnect switch now and was planning to add a second switch to just provide other DC loads without powering the Inverter. The DCLD may be a simpler solution for what I have in mind.


- - Mike
2013 Lounge EXT on 2012 Sprinter

[jim.waters]

Mike,

Have you thought about what kind of switch and where to put it?

Jim

[Boxster1971]

Originally Posted by jim.waters

Mike,

Have you thought about what kind of switch and where to put it?

Jim

It looks like the DCLD is a low current device so any simple toggle switch would work. The Magnum installation manual for the DCLD only requires a 5 amp fuse. I'll have to take some measurements once I get my DCLD. I'd like to mount it on the main control panel in the rear curbside overhead where I have all my other controls.


- - Mike
2013 Lounge EXT on 2012 Sprinter

[BillyBoy]

Sorry to take this thread back to near the beginning, but I just had SB 164 done (before reading all the cautions), and I'm concerned because I'm leaving on a trip where I expect to boondock for a few days and I don't have time to undo anything. I read a post which said that I could pull the fuse for the inverter when it's not being used. Is this advised? And which fuse is it? I see the top slot labeled EMS, so that's my best guess. And if the fuse is pulled, will the fridge and other DC loads still work on my '15 IS? Thanks for any information. The dealer is useless for any help.

[amirm]

You have to disable the relay to save that power. Removing the fuse won't help with that as that relay is in the path of all of your electrical loads.

With the relay in place, and just the fridge and freezer running from 9:00pm on a fully charged battery, plus the fan for a few hours, I woke up at 6:30 with essentially dead batteries at 11.7 volts . Plan to take the relay out of the loop asap.

[Mcrid]

Originally Posted by BillyBoy

Sorry to take this thread back to near the beginning, but I just had SB 164 done (before reading all the cautions), and I'm concerned because I'm leaving on a trip where I expect to boondock for a few days and I don't have time to undo anything.

You can a quick and dirty job by lifting the jump seat, remove the white board//screen and join the red cables on the solenoid to one of the solenoid posts. Then remove the 5 amp fuse they installed. Should be the last one with a blue wire going to it. This will electrically remove the solenoid and return the system operation to the pre SB state. On your trip be sure to keep the inverter turned off unless you need it. You can turn this on and off from the Magnum RC in the overhead control panel. Also, keep your main gas relay turned off unless needed. This will cover you for overnights. You can see one of my photos in the thread where I did this. I went back later and completely removed the relay and extra cabling/wiring.

[LB_3]

^+1.

Just move both power cables to the same post.

[BillyBoy]

A really big Thank You to all for the advice. I assume that moving both red cables to the same post means that I'm essentially connecting them together using the solenoid simply as a buss bar to bind them together?